Method of making water gas



June 2, 1931. o. B. EVANS METHOD OF MAKING WATER GAS Filed April 5, 19243 a 1 b QR 22 FIG].

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//Yl/V7'0 Z2??? 2 Owen Brae 51c Evan's Paten ed June 2, 1931 UNITEDSTATES PATENT OFFICE OWEN B. EVANS, OI PHILADELPHIA, PENNSYLVANIA,ASBIGNOR 'I'O THE U. G. I. 0017- TEACHING COMPANY, OF PHILADELPHIA,PENNSYLVANIA, A CORPORATION 01' nmwm METHOD MAKING WATER GAB Applicationfiled April 8, 1924. Serial No. 703,893.

The efficiency and capacit of a water gas set de nd primarily upon theattainment of a hig temperature in the incandescent fuel bed in thegenerator. This high temperature 5 can be obtained by excessive airblasting but at the expense of the formation of undesirable clinkersdiflicult to remove. The use of superheated air and superheated steamfor obtaining and maintaining that hi h temperature presents mechanicaldi culties which include the maintenance of valves and grates towithstand that temperature.

By my invention the steam and air blast are superheated by the otherwisewasted heat of the products of combustion and of the illuminating gasleaving the apparatus. No valves are subjected to high temperatures. Nohot gases pass through the grate. This permits of the use of amechanical or stationarty grate without requiring water cooling. he hightemperature is produced in the body of the fuel bed where the percentageof ash compared with the percentage of carbon is relatively low and theproduction of this high temperature at this location does not result inthe formation of clinkers difficult to remove.

Generally stated, the invention may be said to comprise the process ofmaking water gas which consists in establishing and maintaining a fuelbed between two carbureters, hot air blasting followed by hot steamingin divided relation in respect to the top and to the portion above thebottom of the fuel bed and in undivided relation in respect to theintermediate portion of the fuel bed and through both carbureters andfirst in one direction and then in the other direction, simultaneouslystoring the heat of secondary combustion and the sensible heat of thewater gas inone of said carbureters, and preheating the air and steam bythe stored heat of the other carbureter, and leadin off bothcomparativel cool water gas an comparatively cool com ustion productsalternately at the outlet of each carbureter.

The invention also comprises the improvements to be presently describedand finally claimed.

In the following description reference will adapted for the practice ofthe invention,

provided with the necessary blast and gas connections (hereinafterdescribed) and with grates 22. The generators contain the fuel bedconsidered as a whole, there being a fuel bed in each generator, but thetwo fuel beds may be conveniently considered as one. The fuel bed isbetween two regenerators shown as carbureters B, B and superheaters A,A, similar to those in common use in water gas manufacture, and thecarbureters may be filled with checkerbrick ormay be empty. The vesselsA, A are both superheaters and stoves and are supplied with checkerbrickfor absorbing or storing and giving up or restorin heat.

ssuming the carbureted water gas set to be in normal operation, theinventlon may be described in connection with it as follows:

All thevalves being closed, blasting is performed b opening the valve 2and stack valve 1, w ereby cold air passes down through the suprhcaterand stove A where it is heated, thence up through the carbureter B whereit is still further heated, and thence into the water gas generator C.Here it divides and part flows up and part flows down (above the grate22) into respectively the top and bottom (above the grate 22) of thewater gas generator C and the division of the up and down air blastingis controlled by the dampers 3 and 4, which being dampers and not valvesare adapted to withstand high heats. In passing through the generators Cand C the air unites with the fuel raising its temperature and bringingit into condition for the decomposition of steam on the succeeding watergas run. From water gas generator 0 the blast gases flow into the top ofthe carbureter B where they are completely burned by the admission ofsecondary air through the valve 6. The products of combustion passthrough the carbureter B and superheater-A heating these vessels and escaping at a com aratively low temperature through the stac valve 1. Ifdesired, secondary air may also be admitted through the valve 5 and theblast gases burned in the vessels. At the conclusion of the heatingperiod or air blow period, valves 2, 5, 6 and 1 are closed, water gasoff-take valve 7 opened and ordinary temperature steam is admittedthrough valve 8 and passes through the apparatus in the same directionas the preceding air blow. In the-passage of the steam through thevessels A and B they are further cooled and the stem is superheated andthen admitted to the fuel in the generators C in a highly heatedcondition. If desired, oil can during this steaming period be admittedthrough valve 9 to carburet the generated water gas. During this steamrun period the net tendency will then be to reduce the tem era-tures invessels A and B, and to raise t e temperatures in the vessels A. and BThe succeeding air blow and steam run is therefore in the oppositedirection. Valves 7, 8 and 9 are closed, valves 10 and 11 opened, andair is admitted through valve 12, then passes through vessels A B C, C,B, A and out through the stack valve 10, secondary air being admittedthrough valves 5 and 13 or either of them as desired to burn the blastgases formed by air blasting the fuel in the water gas generators. Atthe conclusion of this heating period, valves 5, 10, 12 and 13 areclosed, steam is admitted through valve 16, passes through the apparatusin the same direction as the precedmg air blow and by reaction with theincandescent fuel in the water gas generators forms water gas whichpasses out through the water gas valve 11, oil being admitted throughvalve 15 to carburet the water gas. The succeeding air blow and steamrun are in the same direction as at first described.

By thus alternating the direction of both the low and the run throughthe apparatus the air and steam used for gas making are heated to a hightemperature and the Water gas and products of combustion are dischargedfrom the apparatus at low temperatures so that a comparatively largepercentage of the heat generated is retained in the appiaratus and usedfor the purpose of gas ma mg.

When bituminous coal is used the admission of secondary air between thetwo generators as at 5 during the air blasting period will facilitatecarbonization of the raw coal caused by the passage and combustion ofthe blast gases therein and burn the volatile matter evolved in the bodyof a fuel bed thereby storing heat in the fire where it is needed forsubsequent water gas reactions.

From the foregoing description it will be apparent that hot airhavingits full normal content of oxygen is introduced at a portion ofthe fuel bed where the percentage of carbon is comparatively high sothat a region of high temperature appropriate for gas making isprovided, and this region is located in an intermediate part of the fuelbed between its top and bottom. Below this region the hot air has itsoxygen content reduced due to the burning so that where the percentageof ash is high in respect to carbon the latter is burned out at acomparatively low temperature so that the ash is not objectionably fusedto clinker. D'escriptively this region is above the grate. Wherebituminous coal is fed to the top of the fire hot air reaches it quitedirectly so that it is comparatively rapidly carbonized to coke whichdescends into the gas making region of high temperature.

The practice of the invention in connection with the apparatus shown inFig. 2 is as has been described so that the corresponding parts of theapparatus are indicated by the same letters'as in Fig. 1. The differenceis that there is a single water gas generator C instead 'of twogenerators and in consequence there is no air inlet 5, and the processis modified in one or two obvious particulars of which the following maybe mentioned: The incoming hot air blast is introduced centrally of thegenerator at every other blow and the volatile matter distilled from thebituminous coal is burned in the'carbureter B at every other blow.

While-I have referred to hot blasting followed by hot steaming it iswithin my meaning to include hot blasting first in one direction andthen in the other, or. hot steaming first in one direction and then inthe other followed in the first case by additional hot steaming and inthe second case by additional hot blasting. I-

It will be obvious to those skilled in the art to which the inventionrelates that modifications may be made in details of procedure and inmatters of mere form without departing from the spirit of the inventionwhich is not limited as to such matters or otherwise than the prior artand the appended claims may require.

I claim:

1. In the process of manufacture of water gas by alternate air and steamblasting periods; the improvement which consists in providing twoseparate fuel beds-of bituminous fuel in two intercommunicating watergas generators, hot air blasting from the top part of the fuel bed inone generator to the top portion of the other fuel bed in the secondgenerator and from the bottom part of the fuel bed in the firstgenerator to the bottom part of the fuel bed in the second generatorthereby evolving volatile matter in the fuel bed in the first generator,and introducing secondary air between the fuel beds to burn the volatilematter and thereb facilitate the carbonization of raw fuel and to storeheat in the fuel bed in the second generator, and

then generating water gas by steam blasting the heated fuel beds.

2. A process of manufacturing gas as practiced in a set comprising agenerator containing a fuel bed and regenerating vessels connected tosaid generator, which process consists in the following steps: first,passing air through one regenerative vessel, admittin the entire fiow ofair to the center of the fue bed and simultaneously passing a portion ofthe air through the top of the fuel bed and the remaining portion of theair through that portion of the fuel bed adjacent the bottom, and thenpassing the entire flow of air and air blast gases through the secondregenerative vessel thereby heating it; second, re-

versing the flow of air by passing air through the second heatedregenerative vessel, passing the air simultaneously through the top ofthe fuel bed and through that portion of the fuel bed adjacent thebottom and takin off the entire flow of air and air blast gases om themiddle of the fuel bed, and leading the gases through the firstregenerative vessel; third, passing steam through the first regenerativevessel, admitting the entire flow of steam to the center of the fuel bedand simultaneously passing a portion of the steam and the resultingWater gas through the top of the fuel bed and passing the remainingportion of the steam and the resulting water gas through that portion ofthe fuel bed adjacent the bottom, and passing all the resulting watergas through the second regenerative vessel; and fourth, reversing theflow of steam and water gas through the set by passing steam through thesecond regenerative vessel, simultaneously passing a portion of thesteam and the resulting Water gas through the top of the fuel bed andpassing the remaining portion of the steam and the resulting water gasthrough that portion of the fuel bed adjacent the bottom and taking offthe entire flow of steam and resulting water gas from the middle of thefuel bed, and then 1passing the resulting Water gas through the rstregenerative vessel.

OWEN B. EVANS.

